Drafting instrument



Dec. 3, 1946.. O, s, SHAFFER 2,411,981

DRAFTING INSTRUMENT Filed May 11, 1944 2 Sheets-Sheet 1 Inventor By @Mm WWW m Dec. 3, 1946. o, s, S AFFE 2,411,981

' DRAFTING I NS T RUMENT Filed May 11, 1944 2 Sheets-Sheet 2 v Invenfor /7/ V Owens 5W6? v Patented Dec. 3, 1946 2,411,981 DRAFTING INSTRUMENT Owen S. Shaffer, Omaha,

half to Eugene D. OSullivan,

Nebn, assignor of one- Omaha, Nebr.

Application May 11, 1944, Serial No. 535,055

1 Claim.

The present invention relates to new and useful improvements in drafting instruments and more particularly to a device of this character through the use of which section lines or crosshatching may be marked on the drawings at regular and equally spaced distances apart.

An important object of the present invention is to provide a straight edge or ruler having graduations marked thereon at one edge, one end of the ruler haVing a fixed stop and providin an adjust-able stop on the ruler and between which a conventional form of triangle may be positioned, the adjustable stop cooperating with one edge of the triangle to regulate the distance which the triangle may be moved between the stop to determine the distance between the section line or cross-hatching to be drawn at the edge of the triangle.

A further important object is to provide guide means for the adjustable stop which will eliminate play between the adjustable stop and the ruler to a minimum, whereby to promote accuracy in the adjustment of the stop.

A still further object is to provide a device of this character of simple and practical construction, which is neat and attractive in appearance, relatively inexpensive to manufacture and otherwise well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which- Figure 1 is a plan view showing the device in operative position,

Figure 2 is an edge elevational View of the ruler.

Figure 3 is a fragmentary longitudinal sectional view taken substantially on a line 3-3 of Figure 1.

Figure 4 is a transverse sectional View taken substantially on aline 4-4 of Figure 1.

Figure 5 is a perspective view of the adjustable stop.

Figure 6 is a similar view of the slide nut forming part of the adjustable stop.

Figure 7 is a side elevational view of a modified construction for slidably actuating the adjustable stop.

Figure 8 is a transverse sectional view taken substantially on a line 8-8 of Figure 7, and

Figure 9 is a fragmentary longitudinal sectional view taken substantially on a line 99 of Figure 7.

Referring now to the drawings in detail and first with respect to the form of the invention illustrated in Figures 1 to 6, inclusive, the numeral 5 designates a ruler having a fixed stop 6 projecting laterally from one edge thereof, the surface of the ruler being marked with graduations 1 in inches and fractions thereof.

.A longitudinal slot 8 is formed in the ruler adjacent its end opposite from the fixed stop 6, the rear or bottom surface of the ruler, at the edges of, the slot 8, being An adjustable stop extends transversely across the surface of the ruler 5 and is formed at one edge with a flange or elongated head ll adapted to slidably engage one edge of the ruler. The stop I0 is formed at its central portion with an opening I2 through which a set screw I3 is freely inserted, the set screw having threaded engagement in a threaded opening 14 of a rectangularshaped slide block Or nut 15 snugly fitted for sliding movement in the slot 8 and having flanges 16 at its outer surface conformably received in the rabbeted formation 9 of the ruler so that the outer surface of the slide I5 is fiush with the rear surface of the ruler 5 as will be apparent from an inspection of Figure 4 of the drawings.

The flange 1 I of the adjustable stop I0 and the slide l5 cooperate to maintain the side edges of i the stop 10 in substantially true parallelism with the marking forming the graduations I.

In the form of the invention illustrated in Figures 7 to 9, inclusive, the ruler is designated at H having the fixed stop l8 at one end and formed with the longitudinally extending slot l9. One end of the slot 19 is enlarged to receive an anchoring block 20 for a screw 2| which has a ball 22 at one end swivelly received in the block 20, the screw extending longitudinally in the slot l9 and outwardly through the end of the ruler opposite from the fixed stop l8. The outer end of the screw is formed with a manipulating head 23.

The adjustable stop is designated at 24 having the flange 25 at one end slidably engaged with one edge of the ruler and also having a longitudinally extending rib 26 at its intermediate portion slidably engaged in the slot l9. The screw 2| is threaded through the rib 26 whereby a rotary movement of the screw will cause a longitudinal movement of the adjustable stop 24 relative to the ruler I1 in a manner as will be apparent. The surface of the ruler I1 is likewise formed with graduations 21 as heretofore explained for cooperation with the side edges of the adjustable stop 24.

In using the device a conventional form of trirabbeted as shown at 9.

angle 28 is positioned with one edge thereof abutting the ruler 5 between the fixed stop 6 and the adjustable stop It]. The opposite edge of the ruler 5 may be placed against a conventional form of straight edge indicated at 29, if desired. One edge of the triangle 28 is placed in abutting engagement with the fixed stop 6 and the adjustable stop 8 is spaced from the opposite edge of the triangle a desired distance in accordance with the spacing of the section lines or crosshatching to be drawn. The triangle is then moved into abutting engagement with the adjustable stop l0 and the first section line indicated at 30 is then drawn and the triangle then moved toward the left until it engages the fixed stop 6 and the next section line is then drawn parallel to the line 30. The ruler 5 and triangle 28 are then successively moved to continue the marking of the section lines or cross-hatching in a manner as will be apparent.

It is believed that the details of construction and manner of use of the device will be readily understood from the foregoing without further detailed explanation.

Having described the invention, What is claimed as new is:

In a device of the class described for use with a triangle, a straight edge against which the triangle is adapted to be positioned in edge to edge engagement therewith and having an edge stop at one end for engagement by said triangle and a longitudinal slot therein adjacent its other end provided with rabbeted sides, an adjustable stop comprising a member slidably opposed to one side of the straight edge and having a flange overlying and fitting against the edge of the straight edge with which the triangle is adapted to be engaged, a slide fitted in said slot flush with the other side of the straight edge and having edge flanges fitted in said rabbeted sides of the slot, and a screw threaded through said member and slide to clamp the same to the sides of the straight edge.

OWEN S. SHAFFER. 

